Commodore64

When building a logic circuit, you generally also want to know what is happening inside: when a certain conductor goes to logic level "0" or "1" and when a certain flip flop changes state. This analysis will be very useful especially if the circuit operation is faulty. Of course, in certain cases, the logic level will be able to be checked with the help of a logic tester or a simple voltmeter. With a simple voltmeter, however, it will not be possible to check the time sequences of pulses or even the interdependence between different signals, because these can be detected only one at a time. Instead, all the advantages listed above will be...

What JACK Tramiel has to say concerns everyone! No other person has had such a lasting influence on the world of computers as Jack Tramiel. In 1977, he introduced the COMMODORE PET 2001 Personal Electronic Translator, the first personal computer. In 1980, he made computer power affordable for everyone with the VC 20 People's Computer. This was followed in 1982 by the COMMODORE 64, by far the best-selling computer in the world. Tramiel remained true to his motto: "For the masses, not for the classes" and always wanted to offer the latest technology at the lowest prices. This is no different with ATARI, his latest venture, as the ST cle...

by Scott A. Boydman (ScottB30 on QuantumLink) NOTE : The following article also applies to expanding C1700 128K REU's to 512K with the following changes: (1) You will need to remove the 64x1 DRAMS, and replace them with 16 256x1 DRAMS. (2) You will need to cut the "J1", aka "CUT 512K" jumper. This article details the steps required to increase the 1764 RAM Expansion Unit (REU) to a total of 512K. Although the article has been tailored primarily for the GEOS 64 user, it is also applicable to all 1764 REU users who wish a 512K expansion. I have had a great deal of correspondence with people, both by mail and over Quantum-Link, and I wou...

By Andrew E. Mileski Copyright October 3, 1989. In Volume 9, Issue 6 of the Transactor, Paul Bosacki showed us a miracle; the one megabyte C64. Paul had developed an elegant method of allowing the C64 to access this extra memory out of the C64's own memory map. Unfortunately, this extra RAM is rather difficult to access, not all of it is available to the user, and C128 owners cannot expand there machines in the same manner. The circuit necessary for this feat allows a C64 to use 256 k RAM chips, instead of the 64 k RAM chips it was designed to use. Although a brilliantly simple circuit, it is over-kill when one already has a Ram Expan...

(C)opyright Perry M. Grodzinski, 1991 Note: You are free to give away these documents but not to sell! SWIFTLINK is a Trademark of CMD (Creative Micro Designs). Although this project is very simple to construct, some electronic experience would be beneficial. The author takes no responsibility for this modification as this project is to be done at the risk of the reader. With the price of high speed modems quickly falling, home computer users can now have 9600 bits per second modems for the price that 300 BPS once cost. Unfortunately, anything above 2400 BPS for the c64 is a problem, it just can't keep up. Most of the serial to paral...

November 9, 1989 Programmers' Workshop Conference BASIC programmers are spoiled with their OPEN, CLOSE, PRINT, INPUT and GET instructions. In order to perform these functions, the micro- processor must execute hundreds or even thousands of instructions. So, in this conference paper I'm going to give some routines that are hundreds of instructions long to help you get started doing I/O in machine language. Okay? Well... not exactly. You see, Commodore machine language programmers are just a bit pampered too. The C64 has built in 8K bytes of ROM (read only memory) routines dedicated to performing, primarily, input and output fro...

Programmers' Workshop Conference April 5, 1990 by John Leeson The design and use of code or program structures for data used in programming is one of the most important considerations in early software development. This is particularly true for programs which process or use large amounts of data, but can be important in nearly any programming job. Modern programming methods concentrate more emphasis on data structures, and modern programming languages provide more code mechanisms for their design, definition, processing and protection. Machine language, however, being the lowest level of program code, is far removed from the high leve...

by John L 2/11/88 This paper is presented in two parts. Part 1 covers basic ideas and procedures used in debugging: Code reading; using a monitor program; breakpoints; testing; and patching. Part 2 deals with special problems: Debugging interrupt routines; emulation; symbolic debuggers; and debug code. PART 1. Programmers' Workshop Conference, Feb 11, 1988, SYSOP JL Consider first what you will need. A monitor program. The C128 has one built in or you may have a cartridge with one built in. Otherwise load up a monitor program and initialize it before loading your M/L program to work on. A listing of the program you are wor...

On Saturday, the 4 th of May 1996, CMD introduced their newest product, the Super64CPU, to the public at a local GEOS meeting in Vienna/Austria. The Super64CPU has a W65C816S processor with an official clock speed of 20 MHz, inofficially it is supposed to be even a bit higher. The unit I was able to test, was still a beta version prototype. According to CMD in two weeks time (mid of May) the CPU will go into full production (a lot of orders have been already placed), the Super128CPU will follow in mid August (this CPU will be even a bit faster than the C64 version). CMD's Super64CPU comes in a metal case (similar in color and styl...